Maps (on paper or on the screen) are flat surfaces; they require a transformation from the curved surface of the earth to the flat plane: a map projection.

纸上或屏幕上的地图是平面的；它们需要从地球的曲面向平面进行转换：地图投影。

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Map projection in cartography is a way to present a two-dimensional curved surface on a plane, such as a normal map. Figure 2 shows a Traverse Mercator projection.

绘图法中的地图投影方法可以在平面中表示一个两维的曲面，例如一个标准地图。

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A sphere cannot be represented on a flat plane without distortion, which means all map projections distort in one way or another.

球体在平面上不进行扭曲就无法表现出来，这意味着所有制图方式都会以某种方式出现扭曲。

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The defense argued that the incident was a tragic accident caused partly by the fact that the plane's altimeter was not working and the gondola cable that the plane hit was not on the map that he was given.

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In his talk, Teso demonstrated an Android application he built that allowed him to redirect a virtual plane with just a tap on a map application running on his Samsung Galaxy phone.

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Northrop Grumman ( NOC - news - people ) makes an unmanned spy plane called Global Hawk, which can map and image huge areas quickly, but it is expensive, and expensive to fly, and can stay aloft for only a day or so.

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